JPH0326978A - Target tracking apparatus - Google Patents

Abstract

PURPOSE:To eliminate an erroneous assumption by calculating the distance between images in order nearer from an antenna and calculating the locus of a circle from the nearest image to use the same in the determination of the generation position of a false image when a preliminarily stored reflecting body is present on the locus. CONSTITUTION:When image data is stored in an image memory 3, a distance calculation means 5 reads the image data at every azimuth and, when said data comprises a plurality of images, the distance between the image nearest to an antenna 1 and the image immediately therebehind is successively calculated. When a locus calculation means 6 calculates the locus of a circle wherein the distance between the nearest image and the image immediately therebehind is a radius and the nearest image is set at the center thereof, a false image judging means 8 reads the position of the fixed target becoming the reflecting body stored in a reflecting body position setting means 7 and judges the image immediately behind as a false image when said position is present on the locus of the circle. An image data output means 9 erases the false image or adds a discrimination code to the false image to display said image on a display device 4.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a target tracking device, and particularly to the removal of false images.

[Prior Art] Fig. 5 is a diagram illustrating an image displayed on a display of a conventional target tracking device. (referred to as station), (
21) is a cargo ship, (22) is a tanker (23) and (2)
4) is a false image.

For example, a tanker (2l) with a flat surface with strong reflection intensity.
However, if they are fairly close together and the positional relationship is appropriate, the radio waves will be reflected many times and travel back and forth, and each time they will be received by the antenna and become an image, which will display false images (
23) is displayed, or if there is a tanker (22) etc. near the cargo ship <2l>, the radio waves emitted from the own station (20) will be reflected by the tanker (22) and the cargo ship (21
), the reflected wave returns to the local station (20) via the tanker (22) and is received by the tanker (20).
22) A false image is displayed in the posterior position.

Additionally, a false image was displayed at the rear of the cargo ship along a similar route, resulting in misidentification.

Furthermore, there was no device to remove the above-mentioned false images.

[Problems to be Solved by the Invention] In the conventional target object display device as described above, when the reflected waves from the target object are received and displayed on the display device, for example, a tanker or the like having a flat surface with a strong reflection intensity is detected. If the target object is nearby, it will be reflected from that surface and a false image will be displayed behind the target object, and even if it is misidentified, there is a problem in that the false image cannot be removed.

This invention was made to solve this problem, and even if reflected waves from a target object are received, images based on reflected waves from objects that have a surface with a strong reflection intensity near the target object can be discriminated. However, an object of the present invention is to obtain a target object tracking device that can remove that image and display only the true image.

[Means for Solving the Problems] A target object tracking device according to the present invention converts reflected waves from a target object received via an antenna into video data, stores the video data in an image memory, and displays the video data. In a radar device displayed on a device, a reflector position setting means that stores the position of a fixed target included in the video data and a reflector position setting means that reads the video data for each direction from the image memory, and when the read video data includes multiple images. is the distance jl! that sequentially calculates the distance between the image close to the antenna and the image immediately behind it! Set the center in order from the nearest image calculated by the calculation means and the distance calculation means,
A trajectory calculation means that calculates a circular trajectory whose radius is the calculated distance, reads the position of a fixed target stored in the reflector position setting means, and determines whether the fixed target is on the circular trajectory calculated by the trajectory calculation means. If there is a false image, there is a false image determination means that determines the image immediately behind the image centered on the circle as a false image, and a false image determination means that reads the image of the false image determination means and erases the false image if there is a false image, or removes the identification code. and video data output means for outputting the image data to the image memory.

[Operation] In this invention, when the video data is stored in the image memory, the distance calculating means reads the video data for each direction, and if there are multiple videos in the data, the video closest to the antenna and the video immediately behind the antenna are determined. Sequentially calculate the distance between.

Then, when the trajectory calculation means calculates the trajectory of a circle whose radius is the distance between the nearest image and the image immediately behind, and whose center is the nearest image, the false image determination means is stored in the reflector position setting means. The system reads the position of a fixed target that serves as a reflector, and if it is on the circular trajectory, the image immediately behind it is determined to be a false image.

Then, the video data output means reads the video of the determination means, and
The false image is erased or an identification code is added to the false image and outputted to the image memory and displayed on the display.

[Example FIG. 1 is a conceptual diagram showing the configuration of the present invention.

In the figure, (1) is an antenna that emits radio waves to a target and receives the reflected waves, and (2) is an antenna that outputs power to antenna (1) at a predetermined timing and receives the reflected waves from antenna (1). It is a transceiver that converts waves into predetermined video data.

(3) is an image memory that stores video data from the transceiver (2), and (4) is a display that displays the video from the image memory (3>).

(5) is a distance calculation means that reads video data for each direction from the image memory (3), and if there are multiple videos in the read video data, calculate the distance between the video near the antenna and the video immediately behind. are calculated sequentially.

(6) is a trajectory calculating means, which sets the center in order from the closest image calculated by the distance calculating means (5), and calculates a circular trajectory whose radius is the calculated distance.

(7) is a reflector position setting means which stores the position of a fixed target serving as a reflector included in the video data.

(8) is a false image determination means, and reflector position setting means (7)
> reads the position of the fixed target stored in <6>, and if the fixed target is on the trajectory of the circle calculated by the trajectory calculation means <6>, the image directly behind the image centered on the circle is recognized as a false image. It is something to judge.

(9) reads the image of the false image determination means (8), and if there is a false image, erases it or puts an identification code on it and stores it in the image memory (3).
This is video data output means for outputting to.

The target tracking device configured as described above transmits video data of the target received using, for example, a radar device to a transmitter/receiver (2
〉 is stored in the image memory (3〉), the distance till calculation means (5) retrieves the video data for each set direction, determines whether there are multiple images in the video data, and if there are multiple images, , calculate the distance between them.

Using this calculated distance as a radius, the trajectory calculation means (5) calculates the trajectory of a circle based on the set circle equation, with the image close to the antenna (1) as the center.

Once the trajectory of the circle has been calculated, the false image determining means (8) reads the position of the reflector stored in the reflector setting means (7), determines whether there is any reflector on the trajectory of the circle, and detects the reflection. If you have a body,
The image immediately behind the central image is determined to be a false image, and this area is stored.

Next, once the omnidirectional images have been processed based on the set orientation, the video data output means (9) reads the image of the false image determination means (8) and deletes or removes any false images. A code that can identify a false image is added and output to the image memory (3).

Then, the display device (4) displays either a true image free of false images or an image to which a code identifying a false image is added.

FIG. 2 is an embodiment of a schematic configuration diagram showing a specific example of the present invention.

In the figure, (1) to (4) are the same as in Figure 1, and (lO) is an image memory (3) and a CPU (1), which will be described later.
1) The person who interfaces with the output boat.

(1l) corresponds to (5) to (9) in Figure 1 except for (7), and reads the image data stored in the image memory (3) via the input/output port (10). , a CPU that executes predetermined processing.

(l2) corresponds to the reflector position setting means (7),
This is a memory connected to a system bus to the CPU (11).

<13) is the CPU (11) and the reflector human output means (
This is a human output board that interfaces with a keyboard (l4) compatible with 7>.

The target tracking device configured as described above has an antenna (1
) converts the video signal of the target received by the transmitter/receiver (2) into video data and stores the data in the image memory (3), then the CPU (11) stores the data in the image memory (3). Read the video data that is displayed, judge whether there is a false image in the data from the data stored in the memory (l2), erase the false image if there is a false image, and display the display (
4) Display an image without false images.

FIG. 3 is a diagram illustrating an image displayed on a display when the present invention is used, and in the figure, (20) to (24)
is similar to FIG. 5 of the conventional example.

However, since the objects indicated by dotted lines are not displayed on the display (18), false images generated by the tanker (22>, etc.) are erased and only the target object is displayed.

FIGS. 4(a) and 4(b) are flowcharts for explaining the present invention, which will be explained below using the figures.

First, registers are set to retrieve the video data stored in the image memory (12>) for each direction, and initial settings are made to set the equation of the circle and the reflector in the memory (15>) (81). In this case, when using FIG. 3, it is assumed that the settings are made to extract in the order of north, east, south, and west directions, for example.

Then, one screen of image data stored in the image memory is taken out and stored in the memory (12) (S3).

Next, the image data is read from the image memory from the north direction based on the set direction, and the shape and number of images are memorized (S5), and whether there are multiple targets (hereinafter referred to as images) in the read image data. (S7).

If it is determined that there are multiple images, set the radar position 1 (20) of your own station to be the center of the display (4), calculate the distance between each image using it as the starting point (S9), and calculate the distance between each image from the starting point. Set the image located at the minimum distance to the center of the circle (S
ll). In this case, the ship (2l) is the minimum distance.

Next, select the image immediately behind the image set at the center of the circle (
23) Set the distance up to (
S13).

Then, the locus of the circle is calculated from the setting conditions set in the equation of the circle (S15).

Next, a search is made to see if a pre-stored reflector exists on the calculated locus of the circle (817), and it is determined whether the reflector is on the locus (S21). In this case, the tanker (22) is used as a reflector.

Next, if it is determined that there is a reflector, the image immediately behind the image at the center of the circle is determined to be a false image (S24), and the false image is erased (82B). Then, the video area up to the erased false image is stored (S28).

Next, it is determined whether there is any other video (S30), and if there is any video, the end point of the stored video area is calculated (S32).
), set the end point issued by W as the starting point (S34)
. Then, the process moves to step Sll and the process described above is executed.

Further, if it is determined in step 821 that there is no reflector, it is determined whether the radius is the same as the radius of the previous circle (83B), and if it is determined that the radius is not the same as the radius of the previous circle, control is transferred to step S30.

In this case, if the image closest to the antenna (1) is centered, it is determined that the circular trajectories are not the same because they have been calculated only once. For example, the locus of a circle is calculated twice, and if the radius is the same as the radius of the first circle, it is determined that they are the same.

In this case, if it is determined that they are the same, the image centered on the circle this time is determined to be a false image (S37), and step 32
Transfer control to B.

Next, if it is determined in step S30 that there is no other video, it is determined whether omnidirectional video data has been extracted based on the set direction (33g), and if it has not been retrieved, the video data is determined based on the set conditions. , set the next direction in the register (83
9) Return to step S5 and execute the process described above.

÷, if all directions are taken out, video data without artifacts is stored in the image memory (S40), and image memo 3 (3)
The video data is read and displayed (S42), and upon completion, 1+1 is cut off (943). If not finished, step S3
．． Twenty-one.・Move the 1st control, take out the video data of the next screen, and execute the process described in 12 above.

If it is determined in step S7 that there is no plurality of images, the control is transferred to step S38, and the process described above is performed on the actual IR-J.
-R〇 Therefore, by the above processing, a true image without false images can be displayed on the display (4), and there is no possibility of mistaking the false image for the true image.

In addition, although the above-mentioned example was illustrated as a reflector on the circumference, the present invention is not limited to this, and it may be determined whether there is a reflector within the circle by calculating the area of the circle. .

Further, in the above embodiments, the reflector is exemplified as a tanker, but any reflector may be used as long as it has a surface with a strong reflection intensity that can be stored in advance.

Further, in the above embodiment, the false image is erased, but instead of being erased, a code or the like that is determined to be a false image may be added and displayed.

[Effects of the Invention] As described above, according to the present invention, the positions of the images that serve as reflectors are stored in advance, the distances between the images are calculated in order of distance from the antenna, and the distances are used to calculate the circle from the closest image. If a memorized reflector exists on the trajectory, the position of the false image is determined. This method is used to determine the false image, so the image determined to be a false image can be erased or identified, and the image can be identified as a true one. The effect is that there is no misinterpretation of the image.

[Brief explanation of drawings]

Figure 1 is a conceptual diagram showing the configuration of this invention, Figure 2 is an example of a schematic configuration diagram showing a specific example of the invention, and Figure 3 is an image displayed on a display when the invention is used. A diagram explaining
FIGS. 4(a) and 4(b) are flowcharts for explaining the present invention, and FIG. 5 is a diagram for explaining an image displayed on a display of a conventional target tracking device.

Claims (1)

[Claims] (1) In a radar device that converts reflected waves from a target object received via an antenna into video data, stores the video data in an image memory, and displays it on a display, a fixed object included in the video data a reflector position setting means that stores the position of the target, and reads video data for each direction from the image memory, and if the read video data includes multiple videos, one video near the antenna and one immediately behind the antenna are selected. distance calculation means for sequentially calculating the distance of the image; trajectory calculation means for calculating a trajectory of a circle whose radius is the calculated distance by setting the center in order from the closest image calculated by the distance calculation means; and the position of the reflector. The position of the fixed target stored in the setting means is read, and if the fixed target is on the trajectory of the circle calculated by the trajectory calculation means, the image immediately behind the image centered on the circle is determined to be a false image. and video data output means for reading the image of the false image determining means, erasing the false image if there is a false image, or adding an identification code to the image and outputting it to the image memory. A target tracking device featuring: